A Defect Etchant for <100> InGaAsP

Abstract

A defect revealing etching technique for normaln‐normalInGaAsP grown on <100> normalInP by LPE is reported. A chemical solution used with illumination produces protrusions in thin quaternary layers, which correlate well with dislocation pits in underlying and overlying normalInP layers. Using the new etchant, an increase in defect density in the active layer over the defect density in the buffer layer has been detected in lattice matched (≲0.04%) normalInGaAsP/normalInP LED structures.